1. Field of the Invention
This invention relates to a liquid injection recording system in which the bubbling of liquid caused by the power supply for heating of an electro-thermal conversion element is utilized to form flying liquid droplets and the liquid droplets are discharged to a recording medium to thereby accomplish recording of information such as characters, and also relates to a liquid injection recording head, a base plate for the recording head, and a recording apparatus having the liquid injection recording head.
2. Related Background Art
In the liquid injection recording system of the type utilizing heat energy, as the technique for accomplishing smooth harmonious recording over a wider range, there are generally known a technique whereby a heat generation gradient is caused in an electro-thermal conversion element (Japanese Laid-Open Patent Application No. 132258/1980 (U.S. Pat. No. 4,339,762)) and a technique which uses a plurality of electro-thermal conversion elements to which signals can be independently input (Japanese Laid-Open Patent Application No. 132259/1980).
The former harmonious recording system, in which a heat generation gradient is caused in an electro-thermal conversion element, can provide analog harmony in which the amount of liquid injected can be continuously freely changed by continuously changing the driving voltage or the drive pulse width. Accordingly this system has the advantage that it can provide abundant harmony while, on the other hand, it has sometimes suffered from the problem peculiar to the analog system that the amount of liquid injected is varied under the influence of even a slight change in temperature and other external conditions.
In contrast, the latter recording system, using a plurality of electro-thermal conversion elements to which signals can be independently input, is a digital harmonious system and therefore, it is difficult for such system to be affected by external factors such as temperature, etc., but to make the maximize harmoniousness, a number of independent electro-thermal conversion elements must be provided, and this has led to the problem that electrical wiring becomes very complex.